The present invention relates to socket wrenches and in particular to the sockets forming part of such socket wrenches.
It is well known to provide a wrench in the form of a socketed head having a hollow end to fit over a multisided head of a nut or bolt, generally a hexagonally sided nut or bolt. The socket may be permanently attached to an actuating handle in which case generally only one size or at most only two sizes of sockets may be provided, or there is provided a plurality of removable socket heads or as they are more generally called sockets. The latter type of wrench namely one comprising a handle and a plurality of removable sockets is the more commonly provided type of socket wrench since the latter is more versatile allowing a plurality of sizes of nut or bolt to be handled by the one set of sockets. Indeed, the term xe2x80x9ca set of socketsxe2x80x9d is commonly used to include not just the socket heads or sockets per se, but also the combination of the socket heads and the actuating handle, which actuating handle in turn often comprises a rod having pivotally mounted on one end thereof a square sectioned male spud, each individual socket having on the end opposite to its, hexagonally formed portion a square sectioned hole or more properly socket adapted to receive the socket.
The versatility of sets of sockets has long been appreciated, however, the main disadvantage with them is that they tend to be mislaid. There is nothing more frustrating for a workman than to find when he goes to look for a particular socket that it is unavailable to him or her. It may simply have been mislaid previously in which case there is no possibility of using it immediately, or, alternatively it has been mislaid in around the workplace requiring a search to be carried out and therefore delay.
A further minor problem is when one wishes to use more than one size of socket one is forced to carry on one""s person possible sizes of sockets so that they may be available when required.
Another problem with using sets of sockets is that it is necessary to provide a large number of sockets to accommodate a wide range of size of hexagonal bolts and nuts. This problem is exacerbated in countries where previously some other standard for size of bolt head or nut head was used such as imperial rather than the metric sizes more commonly used now.
Attempts have been made in the past to provide a socket for a socket wrench which will overcome these problems. A typical example of these attempts is a socket imitating wrench carrying a plurality of pins which are movable inwards against individual spring biasing so that a bolt head after the socket is pushed onto it is subsequently surrounded by the pins remaining. Such a wrench is sold under the brand name GATOR GRIP. Unfortunately these pins do not provide adequate grip on the bolt head, the pins damage the bold head, the pins do not transmit the torque adequately or positively, the pins fail under high torque and finally, the so-called socket wrench will in many instances grip the nut off centre with respect to the applied torque. Generally speaking it is an unsatisfactory construction.
Other examples of prior art multiple socket wrenches are to be found in U.S. Pat. No. 1,395,528, U.S. Pat. No. 1,626,730 and U.S. Pat. No. 2,453,901. However, these devices only provide a very limited number of sockets and their constructions are such that only such a limited number of sockets are possible in these devices.
The present invention is directed towards overcoming these and other problems.
According to the invention, there is provided a socket for a socket wrench of the type comprising an actuating handle carrying the socket, the socket comprising:
a tubular body,
the body having two opposed end portions on either side of a hollow central portion,
a set of nesting individual sockets on the body at each end of the body, each set of sockets being housed within an end portion of the body,
each adjacent pair of nesting sockets in a set of sockets comprising an inner socket and an outer socket, said inner socket being movable axially inwardly relative to the outer socket to expose said outer socket for use,
an exterior of the body at each end of the body being adapted for engagement with a lever for rotation of the sockets.
It will be appreciated that there is considerable advantage in having sets of nesting sockets on one body in a compact construction, instead of having to carry a large number of separate sockets on one""s person.
Ideally it will be appreciated that there will be more than two nesting sockets. In general there will be a plurality of nesting sockets.
In one embodiment, each nesting socket engages resiliently the other nesting socket or sockets, to require positive disengagement and reinforcement thus preventing the sockets from falling in and out of engagement by providing a force fit of an inner socket within the outer socket. One way of achieving this is to provide on each socket a spring on the outer surface thereof to engage on the inner surface of the next outermost socket. Various forms of springs may be provided such as are often seen conventionally in socket sets being resiliently mounted ball bearings or the like, indeed anything which provides a resistance against relative movement is sufficient.
Ideally the springs when used vary in strength decreasing from the outermost socket to the innermost socket of the set to ensure when the innermost socket is pushed inwards within the other socket, that the other socket it will not carry the outermost sockets with it.
In another embodiment of the invention, each of the nesting sockets is biased outwardly, preferably by means of a spring. For example, each movable socket may be connected to a rear of the outermost socket by means of a helical spring thus providing in the central portion of the outer socket a nest of helical springs each of which biases a corresponding socket outwardly or alternatively they may be biased in a cascade effect.
Ideally, restraining means in the form of a stop are provided to prevent a nesting socket fully withdrawing from its surrounding sockets. The advantage of this is that it is then impossible to lose the sockets of the set.
In one embodiment of the invention, an exposed end of each socket is bevelled inwardly. Further, each successively smaller socket in a nest can be slightly recessed with respect to an adjacent larger socket.
In a particularly preferred embodiment of the invention, there is provided a socket comprising two separate sets of sockets axially spaced apart within an elongate body member and an adaptor for engaging over each end of the body member, the adaptor terminating in an actuating handle engaging socket.
A further advantage in having sockets at both ends is that in addition to providing a versatile range of sockets it is also possible to provide for example metric and imperial sized sockets in the one set which is exceptionally advantageous For example, having fourteen sockets from 6 mm to 32 mm means that while fitting fourteen sizes exactly you are only 1 mm out on the intermediate sizes. The same will apply to imperial sizes.
Ideally each external surface surrounding the end portion is regular sided to form a male portion to engage a female socketed portion of a handle or an adaptor for mounting on the handle. This, it will be appreciated is advantageous, because it means that an easy connection between a handle and the body portion may be achieved.
Ideally the body portion itself has each end portion in the form of a socket thus utilising the body member itself as a socket.
In one embodiment of the invention the handle is a two-part handle comprising a rod having pivotally mounted on one end thereof a square sectioned male spud and a hollow adapter sleeve, one end of which is socketed to engage the external surface of a set of nesting sockets and the other end of which is socketed to receive the male spud. The advantage of this is that now the conventional handle of a conventional set of sockets may be used.
In another embodiment of the invention instead of providing a hollow adapter sleeve the innermost socket of a set of sockets is dimensioned to receive the spud of the handle. In this way it is even more versatile than could be possibly envisaged in that it is now possible to provide in effect a socket that can be used with any conventional actuator handle.
One of the particular advantages of the present invention is that where a wide range of sizes of sockets are required, they can be relatively easily provided.
In a particularly preferred embodiment, locking means is provided for selectively locking each individual socket on the body. Thus advantageously the selected socket wrench element is prevented from retracting on the housing when it is required for use.
In one embodiment the locking means comprises a selector switch on the body which is operable to position an associated selector pin on the housing for engagement with a selected socket wrench element to prevent retraction of the socket wrench element on the body.
Preferably the selector switch is slidably mounted in a circumferential slot in a side wall of the body, the selector switch extending through the slot to engage the selector pin which is mounted within the body.
Conveniently the selector pin is engagable within a number of spaced-apart grooves on an inside face of the body for alignment with each socket wrench element.
Preferably the selector switch is biased outwardly by a spring or the like to positively engage the selector pin in the grooves.
For convenience the selector switch and selector pin are mounted on a switch plate which is engagable in a side wall opening or window in the body.
In another embodiment each socket wrench element has an outwardly extending lug at an inner end of the socket wrench element for engagement with the selector pin.
In a further embodiment said lugs are engagable with an associated land or ledge within the body to retain the socket wrench elements within the body.
In another embodiment a spring is mounted within the body for engagement with the innermost socket wrench element in each set of nesting sockets to urge the sockets outwardly on the body.
Preferably the spring is engagable between the innermost sockets.
In another embodiment an outside face of each end portion of the housing has a hexagonal configuration.
In another aspect, the invention provides a socket as described herein in combination with an adapter having a mounting socket for reception of each end of the body to releasably mount the adapter on the body, said adapter having means for engagement with an actuating lever for rotating the adapter and socket. Preferably, the adapter has a spring loaded locking ball mounted on an inside wall of the mounting socket which is engagable with complementary receiver slots at each end of the body to releasably retain the adapter on the body.